How concerned should I be about this? (Welded Caliper Brackets)
05-13-2009, 07:13 AM
#47
Racer
Think about Lotus car. The body is not welded, it is paste with special epoxy paste. It is not cost effective, but the body is considerably much more stiff as it has been done this way against welded solution.
So, for a "normal" body, it is assume that it has a pre defined durability as it is normally welded. The fact is, if a spindle should have been welded, it would have been much more cost effective, but they decided not to do this way, they even forged it.
So welded that parts as it is in relation with safety, is just the way I can't approve...for me and for the others, as I could be the guys in the another car!
Puyi
05-13-2009, 09:15 PM
#48
Rennlist Member
you are putting your LIFE in the hands of that welder, whoever he is. I would bet that it is strong enough, but you wouldnt catch me in that car on the track.
Just because it has a PCA log book, doesnt mean much of ANYTHING. What it does mean is that the wheel bearings are not loose, belts are date current and you are not leaking fluids and thats about it.
Just because it has a PCA log book, doesnt mean much of ANYTHING. What it does mean is that the wheel bearings are not loose, belts are date current and you are not leaking fluids and thats about it.
05-14-2009, 06:17 AM
#50
Addict
Rennlist Member
Rennlist Member
Some very quick calculations and assumptions
1G decelleration, 1500kG mass, ignore rear wheels, gives retarding force required = 15000N = 7500N per wheel
assume caliper is at 50% of wheel radius - thus reaction at caliper = 2x retarding force at wheel =15000N
Assume weld strength is 100N/mm2 Thats about the same as the allowable bending strength of cast Iron. so it assumes that the welding was undertaken by me (not good at welding)
gives total area of weld requried =150mm2.
Two bolts per caliper threaded into the welded on sockets thus area per individual weld = 75mm2 -say 8mm by 8mm or in English roughly 1/4" by 3/8" .
Posted for now while I go back and look at the OP to guess how big the welds are.
Yeah I'm happy with the above. I may be out by a factor of two but that's still well within allowable stresses for a decent weld.
I'ld still INDT first though and examine regularly for cracks.
1G decelleration, 1500kG mass, ignore rear wheels, gives retarding force required = 15000N = 7500N per wheel
assume caliper is at 50% of wheel radius - thus reaction at caliper = 2x retarding force at wheel =15000N
Assume weld strength is 100N/mm2 Thats about the same as the allowable bending strength of cast Iron. so it assumes that the welding was undertaken by me (not good at welding)
gives total area of weld requried =150mm2.
Two bolts per caliper threaded into the welded on sockets thus area per individual weld = 75mm2 -say 8mm by 8mm or in English roughly 1/4" by 3/8" .
Posted for now while I go back and look at the OP to guess how big the welds are.
Yeah I'm happy with the above. I may be out by a factor of two but that's still well within allowable stresses for a decent weld.
I'ld still INDT first though and examine regularly for cracks.
